Display screen or portion thereof with transitional graphical user interface



FIG. 1 is a front view of a first image in a sequence according to a first embodiment of our design for a Display Screen or Portion Thereof With Transitional Graphical User Interface;

FIG. 2 is a front view of a second image in the sequence thereof;

FIG. 3 is a front view of a third image in the sequence thereof;

FIG. 4 is a front view of a first image in a sequence according to a second embodiment of our design for a Display Screen or Portion Thereof With Transitional Graphical User Interface;

FIG. 5 is a front view of a second image in the sequence thereof;

FIG. 6 is a front view of a first image in a sequence according to a third embodiment of our design for a Display Screen or Portion Thereof With Transitional Graphical User Interface;

FIG. 7 is a front view of a second image in the sequence thereof;

FIG. 8 is a front view of a first image in a sequence according to a fourth embodiment of our design for a Display Screen or Portion Thereof With Transitional Graphical User Interface; and

FIG. 9 is a front view of a second image in the sequence thereof.

The appearance of the transitional image transitions between the images shown in FIGS. 1 through 3 , between the images shown in FIGS. 4 and 5 , between the images shown in FIGS. 6 and 7 , and between the images shown in FIGS. 8 and 9 , respectively. The process or period in which one image transitions to another forms no part of the claimed design.

There is shading which is part of the claimed design. 

CLAIM The ornamental design for a Display Screen or Portion Thereof With Transitional Graphical User Interface, as shown and described. 